US6091615A — Resonant power converter

Claim 1

Independent Claim 255 words

A resonant power converter comprising: a positive bus line (1A); a negative bus line (1B); a power converting portion (2) connected between a DC power source (1) and a load (5) for implementing power conversion, the power converting portion including a plurality of main switching devices (3a-3f) connected in series and provided between the positive bus line and the negative bus line, and a plurality of flywheel diodes (4a-4f) connected in antiparallel with the main switching devices respectively for each phase; a resonant circuit (8) connected between the positive bus line and the negative bus line, and including a resonant capacitor (6) and a resonant reactor (7) connected in series with the resonant capacitor; and control means (13) for switching the main switching devices in accordance with a predetermined pattern to enable the power converting portion to implement power conversion; wherein the control means turns on a first switching device which should turn on based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices to start resonance to be implemented by the resonant capacitor and the resonant reactor, and the control means turns off a second switching device which should turn off based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices when a resonant current caused by the resonance is greater than a load current and hence a current flows through one of the flywheel diodes which is connected in antiparallel with the second switching device.

Claim 2

Dependent Claim 255 words

A resonant power converter comprising: a positive bus line (1A); a negative bus line (1B); a power converting portion (2) connected between a DC power source (1) and a load (5) for implementing power conversion, the power converting portion including a plurality of main switching devices (3a-3f) connected in series and provided between the positive bus line and the negative bus line, and a plurality of flywheel diodes (4a-4f) connected in antiparallel with the main switching devices respectively for each phase; a resonant circuit (8) connected between the positive bus line and the negative bus line, and including a resonant capacitor (6) and a resonant reactor (7) connected in series with the resonant capacitor; and control means (13) for switching the main switching devices in accordance with a predetermined pattern to enable the power converting portion to implement power conversion; wherein the control means turns on a first switching device which should turn on based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices to start resonance to be implemented by the resonant capacitor and the resonant reactor, and the control means turns off a second switching device which should turn off based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices when a resonant current caused by the resonance is greater than a load current and hence a current flows through one of the flywheel diodes which is connected in antiparallel with the second switching device.

Claim 3

Dependent Claim 65 words

A resonant power converter as recited in claim 1, wherein the control means comprises first means for detecting whether or not a voltage between the positive bus line and the negative bus line is negative, and second means for turning off the second switching device when the first means detects that the voltage between the positive bus line and the negative bus line is negative.

Claim 4

Dependent Claim 55 words

A resonant power converter as recited in claim 1, wherein the control means comprises first means for detecting whether or not a voltage across the second switching device is negative, and second means for turning off the second switching device when the first means detects that the voltage across the second switching device is negative.

Claim 5

Dependent Claim 55 words

A resonant power converter as recited in claim 1, wherein the control means comprises first means for detecting whether or not a current flows through the second switching device, and second means for turning off the second switching device when the first means detects that a current does not flow through the second switching device.

Claim 6

Dependent Claim 67 words

A resonant power converter as recited in claim 1, wherein the control means comprises first means for detecting whether or not a current flows through the flywheel diode connected in antiparallel with the second switching device, and second means for turning off the second switching device when the first means detects that a current flows through the flywheel diode connected in antiparallel with the second switching device.

Claim 7

Dependent Claim 30 words

A resonant power converter as recited in claim 1, wherein the control means turns off the second switching device when a predetermined time has elapsed since start of the resonance.

Claim 8

Dependent Claim 35 words

A resonant power converter as recited in claim 1, further comprising over-current avoiding means (9) for preventing an over current from flowing through the main switching devices when the main switching devices are turned on.

Claim 9

Dependent Claim 18 words

A resonant power converter as recited in claim 7, wherein the over-current avoiding means includes a reactor (9a).

Claim 10

Dependent Claim 36 words

A resonant power converter as recited in claim 8, wherein the reactor in the over-current avoiding means has a predetermined inductance chosen not to cause resonance in conjunction with the resonant capacitor and the resonant reactor.

Claim 11

Dependent Claim 40 words

A resonant power converter as recited in claim 9, wherein the inductance Ld of the reactor in the over-current avoiding means, an inductance Lr of the resonant reactor, and an inductance Lm of the load have a relation as Lm>Ld>Lr.

Claim 12

Dependent Claim 50 words

A resonant power converter as recited in claim 8, further comprising a voltage clamp circuit (10) which includes a voltage clamp reactor (10a) coupled with the reactor in the over-current avoiding means for clamping a voltage between the positive bus line and the negative bus line at a predetermined level.

Claim 13

Dependent Claim 30 words

A resonant power converter as recited in claim 11, wherein the voltage clamp circuit returns power to the DC power source by a current flowing through the voltage clamp reactor.

Claim 14

Dependent Claim 87 words

A resonant power converter as recited in claim 12, wherein the control means includes first means for detecting whether or not a current flowing through the voltage clamp reactor is zero, second means for detecting whether or not a current flowing through the voltage clamp reactor is minimum, and third means for starting the resonance when the first means detects that a current flowing through the voltage clamp reactor is zero or the second means detects that a current flowing through the voltage clamp reactor is minimum.

Claim 15

Dependent Claim 58 words

A resonant power converter as recited in claim 7, wherein the over-current avoiding means includes switching means (9b) for disconnecting the power converting portion from the DC power source during a time interval from a moment before start of the resonance to a moment at which the second switching device among the main switching devices is turned off.

Claim 16

Dependent Claim 22 words

A resonant power converter as recited in claim 14, wherein the switching means is able to conduct a current in two ways.

Claim 17

Dependent Claim 34 words

A resonant power converter as recited in claim 1, further comprising a voltage clamp circuit (10) for clamping a voltage between the positive bus line and the negative bus line at a predetermined level.

Claim 18

Dependent Claim 37 words

A resonant power converter as recited in claim 16, wherein the voltage clamp circuit includes a diode (10c) which has an anode connected to the power converting portion and a cathode connected to the DC power source.

Claim 19

Dependent Claim 51 words

A resonant power converter as recited in claim 16, wherein the voltage clamp circuit includes a DC voltage source (10d) connected in series with the DC power source, and a diode (10e) which has an anode connected to the power converting portion and a cathode connected to the DC voltage source.

Claim 20

Dependent Claim 57 words

A resonant power converter as recited in claim 16, wherein the voltage clamp circuit includes a capacitor (10f) connected in series with the DC power source, a diode (10g) which has an anode connected to the power converting portion and a cathode connected to the capacitor, and switching means for charging and discharging the capacitor during clamp.

Claim 21

Dependent Claim 172 words

A resonant power converter comprising: a positive bus line (1A); a negative bus line (1B); a power converting portion (2) connected between a DC power source (1) and a load (5) for implementing power conversion, the power converting portion including a plurality of main switching devices (3a-3f) connected in series and provided between the positive bus line and the negative bus line, and a plurality of flywheel diodes (4a-4f) connected in antiparallel with the main switching devices respectively for each arm; a resonant circuit (8) connected between the positive bus line and the negative bus line, and including a resonant capacitor (6) and a resonant reactor (7) connected in series with the resonant capacitor; and control means (13) for turning on the main switching devices to start resonance to be implemented by the resonant capacitor and the resonant reactor, and for turning off a switching device among the main switching devices when the resonance causes a voltage between the positive bus line and the negative bus line to become substantially 0 V.

Claim 22

Dependent Claim 172 words

A resonant power converter comprising: a positive bus line (1A); a negative bus line (1B); a power converting portion (2) connected between a DC power source (1) and a load (5) for implementing power conversion, the power converting portion including a plurality of main switching devices (3a-3f) connected in series and provided between the positive bus line and the negative bus line, and a plurality of flywheel diodes (4a-4f) connected in antiparallel with the main switching devices respectively for each arm; a resonant circuit (8) connected between the positive bus line and the negative bus line, and including a resonant capacitor (6) and a resonant reactor (7) connected in series with the resonant capacitor; and control means (13) for turning on the main switching devices to start resonance to be implemented by the resonant capacitor and the resonant reactor, and for turning off a switching device among the main switching devices when the resonance causes a voltage between the positive bus line and the negative bus line to become substantially 0 V.

Claim 23

Dependent Claim 98 words

A resonant power converter comprising: a power converting portion (2) including main switching devices (3a-3f) for a plurality of phases, the power converting portion having an upper arm and a lower arm; a resonant circuit (8) connected to the power converting portion, and including a resonant capacitor (6) and a resonant reactor (7) connected to the resonant capacitor; means for short-circuiting the upper arm and the lower arm to each other to enable resonance to be caused by the resonant circuit; and means for switching the main switching devices to implement commutation during a presence of the resonance.

Claim 24

Dependent Claim 98 words

A resonant power converter comprising: a power converting portion (2) including main switching devices (3a-3f) for a plurality of phases, the power converting portion having an upper arm and a lower arm; a resonant circuit (8) connected to the power converting portion, and including a resonant capacitor (6) and a resonant reactor (7) connected to the resonant capacitor; means for short-circuiting the upper arm and the lower arm to each other to enable resonance to be caused by the resonant circuit; and means for switching the main switching devices to implement commutation during a presence of the resonance.

Claim 25

Dependent Claim 36 words

A resonant power converter as recited in claim 21, further comprising short-circuit avoiding means (9) for preventing a short-circuit between the DC power source and the power converting portion during switching of the main switching devices.

Claim 26

Dependent Claim 65 words

A resonant power converter as recited in claim 21, further comprising: a positive bus line and a negative bus line wherein the resonant capacitor and the resonant reactor are connected in series with each other to form a series combination, and the series combination of the resonant capacitor and the resonant reactor is directly connected between the positive bus line and the negative bus line.

Claim 27

Dependent Claim 127 words

A resonant power converter comprising: a power converting portion (2) including upper and lower arms, main switching devices (3a-3f) in the upper and lower arms respectively, and flywheel diodes (4a-4f) connected in antiparallel with the main switching devices respectively; a resonant circuit (8) connected to the power converting portion, and including a resonant capacitor (6) and a resonant reactor (7) connected in series with the resonant capacitor; and control means (13) for short-circuiting the upper and lower arms to each other to enable resonance to be caused by the resonant circuit, and for switching a designated switching device among the main switching devices when the resonance causes a current to flow through one of the flywheel diodes which is connected in antiparallel with the designated switching device.

Claim 28

Dependent Claim 127 words

A resonant power converter comprising: a power converting portion (2) including upper and lower arms, main switching devices (3a-3f) in the upper and lower arms respectively, and flywheel diodes (4a-4f) connected in antiparallel with the main switching devices respectively; a resonant circuit (8) connected to the power converting portion, and including a resonant capacitor (6) and a resonant reactor (7) connected in series with the resonant capacitor; and control means (13) for short-circuiting the upper and lower arms to each other to enable resonance to be caused by the resonant circuit, and for switching a designated switching device among the main switching devices when the resonance causes a current to flow through one of the flywheel diodes which is connected in antiparallel with the designated switching device.

Claim 29

Dependent Claim 51 words

A resonant power converter as recited in claim 24, wherein the control means includes timing detection means (161) for detecting desired timings at which the main switching devices are switched, and means (162) for short-circuiting the upper and lower arms to each other at timings equal to the detected desired timings.

Claim 30

Dependent Claim 34 words

A resonant power converter as recited in claim 24, wherein the control means includes means for turning on all the main switching devices to implement short-circuiting the upper and lower arms to each other.

Claim 31

Dependent Claim 65 words

A resonant power converter as recited in claim 24, further comprising a positive bus line and a negative bus line, wherein the resonant capacitor and the resonant reactor are connected in series with each other to form a series combination, and the series combination of the resonant capacitor and the resonant reactor is directly connected between the positive bus line and the negative bus line.

Claim 32

Dependent Claim 265 words

A resonant power converter comprising: a positive bus line; a negative bus line; a power converting portion connected between a DC power source and a load for implementing power conversion, the power converting portion including a plurality of main switching devices connected in series and provided between the positive bus line and the negative bus line, and a plurality of flywheel diodes commented antiparallel with the main switching devices respectively for each phase; a resonant circuit connected between the positive bus line and the negative bus line, and including a resonant capacitor and a resonant reactor connected in series with the resonant capacitor; and control means for switching the main switching devices in accordance with a predetermined pattern to enable the power converting portion to implement power conversion; wherein the control means turns on a first switching device which should turn on based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices to start resonance to be implemented by the resonant capacitor and the resonant reactor, and the control means turns off a second switching device which should turn off based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices; and wherein the control means comprises first means for detecting whether or not a voltage between the positive bus line and the negative bus line is negative, and second means for turning off the second switching device when the first means detects that the voltage between the positive bus line and the negative bus line is negative.

Claim 33

Dependent Claim 265 words

A resonant power converter comprising: a positive bus line; a negative bus line; a power converting portion connected between a DC power source and a load for implementing power conversion, the power converting portion including a plurality of main switching devices connected in series and provided between the positive bus line and the negative bus line, and a plurality of flywheel diodes commented antiparallel with the main switching devices respectively for each phase; a resonant circuit connected between the positive bus line and the negative bus line, and including a resonant capacitor and a resonant reactor connected in series with the resonant capacitor; and control means for switching the main switching devices in accordance with a predetermined pattern to enable the power converting portion to implement power conversion; wherein the control means turns on a first switching device which should turn on based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices to start resonance to be implemented by the resonant capacitor and the resonant reactor, and the control means turns off a second switching device which should turn off based on the gate signal command, the output signal of the gate signal circuit, among the main switching devices; and wherein the control means comprises first means for detecting whether or not a voltage between the positive bus line and the negative bus line is negative, and second means for turning off the second switching device when the first means detects that the voltage between the positive bus line and the negative bus line is negative.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2003-07-18	2004-01-17	2004-07-18	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2007-07-18	2008-01-17	2008-07-18	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2011-07-18	2012-01-17	2012-07-18	$7700.00	Window Closed / Lapsed

Resonant power converter

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag